A healthy Curiosity spent Sol 4, its fifth day on Mars, preparing for this weekend's planned "brain transplant"--transitioning to a new version of flight software on both of Curiosity's redundant main computers. The new software is better suited for Mars surface operations, such as driving and using Curiosity's robotic arm. The "brain transplant" will take place during a series of steps beginning this evening and continuing through Aug. 13. The new software was uploaded to the rover's memory during the Mars Science Laboratory spacecraft's flight from Earth. Key capabilities in the new software enable full use of Curiosity's powerful robotic arm and drill, and advanced image processing to check for obstacles while driving. This will ultimately allow Curiosity to make longer drives by giving the rover more autonomy to identify and avoid potential hazards and to drive along a safe path that the rover identifies for itself.

The flight team elected to defer further science activities until after the flight software transition is completed. Several Mastcam color images were downlinked. The mission's science team is busy analyzing images Curiosity has taken of its surroundings, and is discussing features of interest that they will investigate in a few weeks once initial checkouts of the rover and the landing site are completed.

Curiosity awoke from her "beauty sleep" today to the toe-tapping tune "Good Morning" from the musical "Singing in the Rain," feeling healthy and refreshed and ready for a busy day of continued health checks and imagery. The rover continues to perform very well. Today's Sol 3 morning and afternoon passes by NASA's Mars Odyssey and Mars Reconnaissance Orbiter spacecraft provided a plethora of new data, including more high-resolution black-and-white 360-degree and deck panorama images from her Navigation Camera, or Navcam, which revealed some small pebbles deposited on the deck during landing, which should pose no problems for mission operations. Curiosity also returned 130 low-resolution thumbnail images from the color Mast Camera, or Mastcam, providing scientists and engineers with their first color panorama glimpse of Gale Crater.

Curiosity's day began with a "beep" from its low-gain antenna, telling the flight team that their master sequence of activities for that sol was successfully activated from the ground. The flight team then uploaded files to the rover's remote electronics unit memory in preparation for the upcoming Sol 5 upgrade of Curiosity's software to optimize Curiosity for surface operations. Curiosity's backup computer was then powered on and successfully checked out. The Radiation Assessment Detector instrument is operating as planned and collected additional data on surface radiation. The Mastcam is operating as planned and successfully executed its 360-degree and calibration target observations. In addition, early checkouts of the Alpha Particle X-ray Spectrometer (APXS), Chemistry & Mineralogy Analyzer (CheMin), Sample Analysis at Mars (SAM), and Dynamic Albedo Neutrons (DAN) instruments were all successful. The mission's science team began creating a geological map of about 150 square miles (about 390 square kilometers) within Gale Crater, including the landing area.

After waking up to the rousing refrains of the Beatles' "Good Morning Good Morning," a healthy Curiosity continued checking out her systems and returning amazing imagery. The Sol 2 morning and afternoon UHF communications passes from NASA's Mars Odyssey and Mars Reconnaissance Orbiter spacecraft provided significant new data, including spectacular full-frame images of the Mars Science Laboratory's descent through the Martian atmosphere by Curiosity's Mars Descent Imager (MARDI) instrument. Other imagery included full-frame views from the rover's navigation cameras, or Navcams, looking at the rim of Gale Crater; the first, lower-resolution thumbnail 360-degree view of Curiosity's new surroundings in Gale Crater; deck pan images of the rover herself; and images of the Martian surface next to the rover. Another image set, courtesy of the Context Camera, or CTX, aboard NASA's Mars Reconnaissance Orbiter, has pinpointed the final resting spots of the six, 55-pound (25-kilogram) entry ballast masses. These tungsten masses impacted the Martian surface at high speed, about 7.5 miles (12 kilometers) from Curiosity's landing location.

The rover's high-gain antenna was successfully pointed toward Earth. Its 3.6-foot-tall (1.1-meter) remote sensing mast was deployed, and range of motion was successfully tested. Surface radiation data were acquired from the Radiation Assessment Detector (RAD) instrument but have not yet been downlinked. Curiosity's temperatures are running a bit warmer than expected; however, the flight team believes this is because Gale Crater is simply a bit warmer than originally predicted.

August 7: Curiosity Gets More Looks at its Surroundings; Health Checks Continue

Curiosity is healthy as it continues to familiarize itself with its new home in Gale Crater and check out its systems. The team's plans for Curiosity checkout today included raising the rover's mast and continued testing of its high-gain antenna, whose pointing toward Earth will be adjusted on Sol 2. Science data were collected from Curiosity's Radiation Assessment Detector, and activities were performed with the Rover Environmental Monitoring Station instrument. Curiosity transmitted its first color image from the surface of Mars, from the Mars Hand Lens Imager, or MAHLI, showing part of the north rim of Gale Crater. Additional calibration images were received from Curiosity's Navcam and Mastcam. All systems are go for deployment of the rover's remote sensing mast on Sol 2, followed by a 360-degree pan by the rover's Navcam. The Mastcam will also be calibrated against a target image on the rover. NASA's Mars Reconnaissance Orbiter returned a spectacular image of Curiosity's landing site, depicting the rover, parachute, back shell, heat shield and descent stage. Data were received from both NASA's Mars Reconnaissance Orbiter and Mars Odyssey.

Aug. 6: Curiosity Safely on Mars! Health Checks Begin
With Curiosity now safely on the surface of the Red Planet after last night's spectacular entry, descent and landing in Gale Crater, NASA's Mars Science Laboratory begins its planned primary one-Martian-year (98-week) mission of discovery and exploration.

On its first Martian day, designated Sol 0, the rover is checking its health and measuring its tilt. All Sol 0 spacecraft activities appear to have been completely nominal. These include firing all of Curiosity's pyrotechnic devices for releasing post-landing deployments. Spring-loaded deployments, such as removal of dust covers from the Hazard-Avoidance cameras (Hazcams) occur immediately when pyros are fired. Curiosity also took images with its front and rear Hazcams both before and after removal of the dust covers, checked out its UHF telecommunications system and rover motor controller assembly, and completed all activities required to proceed with its planned activities on Sol 1. Approximately five megabytes of data were successfully relayed back to Earth from NASA's Mars Odyssey spacecraft during its overpass today.

Curiosity landed facing east-southeast within Gale Crater, with a heading of 112.7 degrees (plus or minus five degrees), and a few degrees of tilt. A Sol 1 overpass by Mars Odyssey will provide additional information on Curiosity's position and additional imagery. A first look at some color images taken just before landing by MSL's Mars Descent Imager also provided additonal information on the rover's precise location.

Activities planned for Sol 1 during the mission's approximately one-month characterization activity phase include deploying Curiosity's high-gain antenna, collecting science data from Curiosity's Radiation Assessment Detector and Rover Environmental Monitoring Station instruments, and obtaining additional imagery. The mission's characterization activity phase is design to learn how all Curiosity's subsystems and instruments are functioning after landing and within the environment and gravitational field of Mars.

Aug. 5: Curiosity Set for Mars Landing Tonight

Its approximately 352 million mile (567 million kilometer), 36-week journey from Earth nearly complete, NASA's Mars Science Laboratory spacecraft and its Curiosity rover are "all systems go" for touchdown in Mars' Gale Crater tonight at 10:31 p.m. PDT (1:31 a.m. EDT Aug. 6). This morning, flight controllers decided to forgo the sixth and final opportunity on the mission calendar for a course-correction maneuver. The spacecraft is headed for its target entry point at the top of Mars' atmosphere precisely enough that the maneuver was deemed unnecessary. In addition, this afternoon, mission controllers determined that no further updates are necessary to the onboard information the spacecraft will use during its autonomous control of MSL's entry, descent and landing. Parameters on a motion tracker were adjusted Saturday for fine-tuning determination of the spacecraft's orientation during its descent.

As of 6:18 p.m. PDT (9:18 p.m. EDT), MSL was approximately 36,000 miles (57,936 kilometers) from Mars, traveling at a speed of about 8,400 mph (about 3,755 meters per second).

Aug. 4: Curiosity Closes in on its New 'Home'
With Mars looming ever larger in front of it, NASA's Mars Science Laboratory spacecraft and its Curiosity rover are in the final stages of preparing for entry, descent and landing on the Red Planet at 10:31 p.m. PDT Aug. 5 (1:31 a.m. EDT Aug. 6). Curiosity remains in good health with all systems operating as expected. Today, the flight team uplinked and confirmed commands to make minor corrections to the spacecraft's navigation reference point parameters. This afternoon, as part of the onboard sequence of autonomous activities leading to the landing, catalyst bed heaters are being turned on to prepare the eight Mars Lander Engines that are part of MSL's descent propulsion system. As of 2:25 p.m. PDT (5:25 p.m. EDT), MSL was approximately 261,000 miles (420,039 kilometers) from Mars, closing in at a little more than 8,000 mph (about 3,600 meters per second).Aug. 3: MSL Right on Course - TCM-5 Cancelled
With less than three days to go before touchdown on the Red Planet, Curiosity remains in good health, with all systems operating as expected. Given the Mars Science Laboratory spacecraft's consistent and stable course, today the project decided that the planned Trajectory Correction Maneuver 5 (TCM-5) and its corresponding update to parameters for the autonomous software controlling events during entry, descent and landing will not be necessary. As of 12:35 p.m. today PDT (3:35 p.m. EDT), the Mars Science Laboratory spacecraft was approximately 468,000 miles (753,200 kilometers) from Mars, or a little less than twice the distance from Earth to the moon. It is traveling at about 8,000 mph (3,576 meters per second). It will gradually increase in speed to about 13,200 mph (5,900 meters per second) by the time it reaches the top of the Martian atmosphere.

Aug. 2: MSL Remains on Track for Weekend Landing
Curiosity remains in good health, with no significant issues currently in work. There are no real-time activities planned today. The Mars Science Laboratory spacecraft remains on a consistent and stable course, well within the limits required to reach its target landing ellipse. As a result, yesterday the flight team decided to cancel the build and test of a contingency version of Trajectory Correction Maneuver 5. This contingency manuever, had it been needed, would have been used in the event an emergency prevented the team from executing the nominal scheduled TCM-5 maneuver, which is planned for Friday, Aug. 3, if needed. The project also canceled a corresponding update to parameters for the autonomous software controlling events during entry, descent and landing.

Aug. 1: Further Preps for Entry, Descent and Landing
With Curiosity now flying under the control of the autonomous entry, descent and landing timeline, the Mars Science Laboratory team continues to monitor the spacecraft's health and trajectory. There are no real-time activities planned today. In the event that a fifth trajectory correction maneuver is needed to further fine-tune the spacecraft's course to reach its target landing ellipse, the flight team is making preparations for it. If needed, that maneuver would be executed on Friday, Aug. 3. Curiosity remains in good health, with no significant issues currently in work.

July 31: Entry, Descent and Landing Timeline Activated
The Mars Science Laboratory continues its final preparations for entry, descent and landing this upcoming weekend. Yesterday, the flight team completed and confirmed a memory test on the software for the mechanical assembly that controls MSL's descent motor. They also configured the spacecraft for its transition to entry, descent and landing approach mode, and they enabled the spacecraft's hardware pyrotechnic devices. MSL is now under the control of the autonomous entry, descent and landing timeline flight software. The flight team continues to monitor Curiosity's onboard systems and flight trajectory. The spacecraft and ground systems remain in good health, with no significant issues currently being worked.

July 30: Entry, Descent and Landing Procedure Begins
Today, the Mars Science Laboratory flight team begins executing its procedure for entry, descent and landing (EDL), and the spacecraft begins its sequence of autonomous activities leading to the landing this coming weekend. These activities include enabling needed components and setting final parameters. In addition, the schedule over the next several days includes opportunities to update parameters for the autonomous software controlling events during EDL. If needed, these updates can fine-tune the spacecraft's autonomous controls for its descent through the atmosphere. Some parameters give the spacecraft's onboard computer knowledge about where the vehicle is relative to Mars. Others may be updated based on observations by NASA's Mars Reconnaissance Orbiter spacecraft of Mars' variable atmospheric conditions in this week before landing.

July 29: Course Maneuver Successful; MSL Begins Final Approach
Late Saturday night, NASA's Mars Science Laboratory spacecraft successfully fine-tuned its course to better zero in on its target entry point into the Martian atmosphere on landing day. Two brief thruster firings totaling about six seconds altered the spacecraft's velocity slightly, by about one-fortieth of one mile per hour (one centimeter per second). This trajectory correction maneuver the fourth since MSL's launch adjusted the point at which Curiosity will enter the Martian atmosphere by about 13 miles (21 kilometers). On landing day, MSL can steer enough during its flight through the upper atmosphere to correct for a miss of the target entry point by a few miles and still land within its target ellipse. Mission engineers and managers rated the projected 13-mile miss big enough to warrant a correction maneuver. Telemetry and tracking data indicate the maneuver was successful. MSL will have two further opportunities for additional course corrections during the final 48 hours before landing, if needed.

July 28: MSL Set to Begin Final Approach
Tonight the Mars Science Laboratory spacecraft is scheduled to perform a very small course adjustment, called Trajectory Correction Maneuver 4 (TCM-4). Around 10 p.m. PDT (1 a.m. EDT), two brief thruster firings totaling about six seconds will adjust the spacecraft's trajectory to better hone in on Curiosity's target entry point into the Martian atmosphere. This course adjustment will be the fourth performed during MSL's journey between Earth and Mars. The maneuver will turn the spacecraft to its final attitude and mark the start of Curiosity's final approach to the Red Planet.

July 27: MSL Telemetry Monitoring, Trajectory Tracking Continue
The flight team continues to monitor the Mars Science Laboratory spacecraft's telemetry and track its trajectory. There are no real-time spacecraft activities planned today. Late tomorrow night, the spacecraft is scheduled to perform its fourth and smallest trajectory correction maneuver, which will mark the beginning of MSL's final approach to Mars.

July 26: MSL Configured for Final Approach; Flight Team Takes a Breath
With completion of nearly all work to configure the Mars Science Laboratory spacecraft for entry, descent and landing, most of the flight team is getting some well-deserved rest today in preparation for next week's final approach to Mars. There are no planned flight team spacecraft activities today. NASA's Deep Space Network continues to monitor spacecraft telemetry and track the spacecraft's trajectory.

July 25: MSL's Terminal Descent Radar System Gets a Checkout
Today, the Mars Science Laboratory's terminal descent sensor is being checked out in preparation for Curiosity's entry, descent and landing. The sensor is a radar system that is mounted on MSL's descent stage. Following separation of MSL's heat shield at an altitude of approximately 5 miles (8 kilometers) and a velocity of approximately 280 mph (125 meters per second), the sensor begins collecting data on the spacecraft's velocity and altitude in preparation for landing.

July 24: Curiosity's Batteries Get a Charge
Today, Curiosity's two lithium ion rechargeable batteries are being recharged to 100 percent of capacity in preparation for entry, descent and landing. The batteries, which have been maintained at a 70-percent state of charge during the cruise to Mars, are being recharged using power from Mars Science Laboratory's cruise-stage solar array. The batteries enable Curiosity's power subsystem to meet peak power demands of rover activities when the demand temporarily exceeds the onboard multi-mission radioisotope thermoelectric generator (MMRTG) steady output level. With a capacity of about 42 amp-hours each, the batteries are expected to go through multiple charge-discharge cycles per Martian day.

July 23: Prepping MSL's Descent Stage Navigation System for Landing
Preparations continue for Curiosity's entry, descent and landing and surface operations. Today, the two inertial measurement units (IMUs) in Mars Science Laboratory's descent stage are being configured, along with other guidance and control parameters for entry, descent and landing. The IMUs are electronic devices that will be used to maneuver the spacecraft's descent stage, measuring and reporting on its velocity, orientation and gravitational forces. The descent stage does its main work during the final few minutes before touchdown on Mars, providing rocket-powered deceleration and two bands of telecommunications for the final phase of MSL's arrival at Mars that includes lowering the Curiosity rover on a bridle and continuing descent until rover touchdown. In addition, more communications parameter updates for Curiosity's surface operations are being uploaded to Curiosity's main computers.

July 22: Trajectory Tracking Continues
Engineers at NASA's Deep Space Network continue to run differential ranging track passes to track Mars Science Laboratory's trajectory. These activities are designed to more closely track the spacecraft's trajectory and position as it draws nearer to the Red Planet and Mars' gravitational influence on the spacecraft increases.

July 21: Getting a Better Bead on Trajectory
Today, engineers at NASA's Deep Space Network are running two differential ranging track passes to track Mars Science Laboratory's trajectory. These activities are designed to more closely track the spacecraft's trajectory and position as it draws nearer to the Red Planet and Mars' gravitational influence on the spacecraft increases.

July 20: Curiosity Completes Week of Onboard Computer Preps
As of yesterday evening, the week-long reboot and configuration activities on Curiosity's two redundant main computers, or Rover Compute Elements -- including the uplink of spacecraft configuration parameters for entry, descent and landing -- were completed, a day ahead of schedule. Today, backup software for Curiosity's entry, descent and landing is being configured onboard the Mars Science Laboratory spacecraft. In case Curiosity's prime computer resets for any reason during the critical minutes of entry, descent and landing, this backup software is designed to enable Curiosity's backup computer to promptly take control and finish the landing with a bare-bones version of entry, descent and landing instructions.

July 19: More Computer Preps for Curiosity
With updated flight sequences and communications parameters for entry, descent and landing and surface operations now uploaded to one of Curiosity's two redundant main computers -- Rover Compute Element (RCE)-B -- today RCE-A is being swapped back to become Curiosity's prime computer, and RCE-B is returning to backup mode. Prime computer RCE-A will then receive its own set of updated flight sequences and communications parameters.

July 18: Curiosity Continues Computer Preps, Gets 'Attitude Adjustment'
Activities continue to prepare Curiosity's redundant main computers, or Rover Compute Elements, for arrival at Mars. Today, Curiosity's RCE-A computer, which was swapped with the backup computer yesterday, is being cold reset, or rebooted, while in online, or backup, mode. Work continues to upload updated flight sequences and communications parameters for Curiosity's entry, descent and landing and surface operations to the spacecraft. In addition, mission controllers yesterday completed the 21st attitude control turn on the Mars Science Laboratory spacecraft, a day early. This turn adjusts the spacecraft's orientation to keep its medium-gain antenna pointed toward Earth for communications. This was the second-to-last attitude control turn planned before landing day.

July 17: Curiosity Swaps Computers, Gets Updated Arrival Data
Activities continue through July 20 to prepare Curiosity's redundant main computers, or Rover Compute Elements, for arrival at Mars. Today, the computer that has been operating as Curiosity's prime computer is being swapped with the backup computer. On Wednesday July 18, that computer will be cold reset, or rebooted, while in online, or backup mode, following the same process used to cold reset the redundant computer on July 16. In addition, beginning today and continuing through July 20, updated flight sequences and communications parameters for Curiosity's entry, descent and landing and surface operations will be uploaded to the spacecraft.

July 16: Curiosity Computer Preps for Arrival
Beginning today, Curiosity's redundant main computers, or Rover Compute Elements, will be power-cycled while in the online, or backup mode. The process, called a cold reset, reboots the computer, resetting it to a predictable, default state prior to the mission's arrival at Mars. This activity begins today with the reboot of the backup computer while in the online state and will continue through July 20. Tomorrow, the prime and backup computers will be swapped, and the reboot process will be repeated on Thursday with the other computer.

July 13: Radiation Instrument Finishes Inflight Measurements
The Radiation Assessment Detector instrument on Curiosity has finished the measurements it had been making during its flight from Earth to Mars. It will be configured for surface operations and turned off today and remain turned off until after landing.

July 12: MSL Team Has Final Test of Landing Procedures
Today, the Mars Science Laboratory flight team is conducting a final operations readiness test of entry, descent and landing procedures in preparation for Curiosity's landing on Aug. 5, PDT.

July 11: MSL Complete Turn
The Mars Science Laboratory Spacecraft completed an attitude control turn today, adjusting its orientation for keeping its medium-gain antenna pointed toward Earth for communications. This was the third-to-last attitude control turn planned before landing day.